The world's largest concentration of nukes is housed 20 miles NW of Seattle, and it's defended by trained dolphins.

Naval Base Kitsap, a marine base 20 miles from Seattle, may be home to the world's largest single-location arsenal of nuclear weapons, and it's defended by dolphins trained by the US Navy."Nearly one-quarter of America's 9,962 nuclear weapons are now assigned to the Bangor submarine base on Hood Canal, 20 air miles northwest of downtown Seattle," the Seattle Times reported in 2006.
Bangor was the name of a base that merged with another to form Kitsap in 2004.
"This makes Bangor the largest nuclear weapons storehouse in the United States, and possibly the world," according to the Seattle Times.
The United States' stockpile of nuclear weapons has fallen since 2006 thanks to a series of disarmament agreements with Russia. But most of those about which details are publicly known are equipped for launch via submarine, according to The Economist.
That explains why so much of the US stockpile would be positioned in a naval base on the Pacific Ocean, a part of the world towards which the US is in the midst of a strategic pivot.
Navy spokesman Chris Haley told Business Insider that the US Navy has used dolphins to defend the waters around the base since May 2010. Before then, according to another Navy spokesman, trained sea lions were also used to detect unwanted swimmers.
The Navy Marine Mammal Program at the Space and Naval Warfare Systems Command (or SPAWAR) in San Diego, California currently trains 85 dolphins and 50 sea lions for service in the US Navy.